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The McGuire Fire, located in central Idaho, burned nearly 43,500 acres during it�s lifespan,
which began in late August of 2012. As a result of this intensely burnt area of terrain, flash
flooding could become a major threat, especially for the town of Dixie. The following is information
on the potential impacts from flash flooding that may occur.
The McGuire Fire, located in central Idaho, burned nearly 43,500 acres during it�s lifespan,
which began in late August of 2012. As a result of this intensely burnt area of terrain, flash
flooding could become a major threat, especially for the town of Dixie. The following is information
on the potential impacts from flash flooding that may occur.
The area pictured here in orange is the terrain that was severely damaged by the McGuire Fire.
Rainfall runoff will accumulate in the Crooked Creek watershed, directly affecting Crooked
Creek, which runs through the town of Dixie. This is the particular area of interest, should
flash flooding occur. Here is an example of what the terrain looks
like in and around where the McGuire Fire blazed. You can see that the heavily scorched
terrain has little vegetation left to soak up future rain. This type of burn scar is
what primes locations such at this for the high potential to see flash flooding.
So what type of rainfall is necessary for burn scar flash flooding? The main type of
rain is high intensity rainfall produced by thunderstorms, either from individual thunderstorms,
or a line of thunderstorms training over the burn area. This could definitely produce a
flash flood scenario, which, for the McGuire Burn Area, will be one half an inch of rain
or more in 30 minutes. The other type of rainfall that could occur over the burn area will be
stratiform rainfall. This will be a prolonged period of steady rainfall, which could last
a few days. If this occurs, it will NOT yield a flash flood scenario. Why? Because we NEED
high intensity rainfall. This is the most important thing to remember.
Here is a video showing a flash flood that occurred over a different burn area, which
had the same threshold as the McGuire Fire. This was the result of having met that threshold.
Please press the �arrow� button to begin the movie.
Now let�s take a closer look at the Crooked Creek watershed, and how flash flooding could
potentially impact residents of Dixie, particularly those living close to Crooked Creek.
This is a zoomed in image of downtown Dixie, which could be directly affected by flash
flooding along Crooked Creek, which as you can see from the arrows, runs very closely
to homes, businesses, and frequently traveled roadways. Should flash flooding occur, damage
to structures and closure of roadways are likely due to high water and debris flows.
Rock washouts from upstream could deposit across portions of Main Street and Airway
Drive. If the washouts are large enough, road closures could occur, causing residents to
use alternate travel routes for a time. If you have any further questions on flash
flood potential from the McGuire Fire burn area, please call us at: 406-329-4840, or
go to our website at: www.weather.gov/missoula.